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潘三矿 1.8 Mta 初步设计 浅析 深井 巷道 支护 技术

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潘三矿1.8Mta新井初步设计浅析深井巷道支护技术,潘三矿,1.8,Mta,初步设计,浅析,深井,巷道,支护,技术

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中 国 矿 业 大 学本科生毕业设计姓 名： 韩效辉 学 号： 01060099 学 院： 矿业工程学院 专 业： 采矿工程 设计题目： 潘三矿1.8Mt/a新井初步设计 专 题： 浅析深井巷道支护技术 指导教师： 常庆粮 职 称： 讲师 2010年6月 徐州中国矿业大学毕业设计任务书学院 矿业工程学院 专业年级 采矿工程06级 学生姓名 韩效辉 任务下达日期：2010年 3月1日毕业设计日期： 2010 年 3月1日至 2010年6月15日毕业设计题目：潘三矿1.8Mt/a新井初步设计毕业设计专题题目：浅析深井巷道支护技术毕业设计主要内容和要求：毕业设计主要内容包括一般部分、专题部分和翻译部分。还要绘制五张大图，分别为矿井开拓平面图、矿井开拓剖面图、采区巷道布置平面图、采区巷道布置剖面图、采煤方法图。一般部分是按潘三矿的实际地质条件，完成潘三矿1.8Mt/a新井初步设计的主要内容，毕业设计一般部分必须按照毕业设计大纲的要求进行，完成大纲规定的全部工程量。毕业设计的专题部分是针对理论上或生产实际中某一具体问题进行较为深入细致的设计和研究。完成这部分内容时，应尽量发挥自己的创造能力，在内容，方法或结论的某一方面尽可能的创新。院长签字： 指导教师签字：中国矿业大学毕业设计指导教师评阅书指导教师评语（基础理论及基本技能的掌握；独立解决实际问题的能力；研究内容的理论依据和技术方法；取得的主要成果及创新点；工作态度及工作量；总体评价及建议成绩；存在问题；是否同意答辩等）：成 绩： 指导教师签字： 年 月 日中国矿业大学毕业设计评阅教师评阅书评阅教师评语（选题的意义；基础理论及基本技能的掌握；综合运用所学知识解决实际问题的能力；工作量的大小；取得的主要成果及创新点；写作的规范程度；总体评价及建议成绩；存在问题；是否同意答辩等）：成 绩： 评阅教师签字： 年 月 日中国矿业大学毕业设计答辩及综合成绩答 辩 情 况提 出 问 题回 答 问 题正 确基本正确有一般性错误有原则性错误没有回答答辩委员会评语及建议成绩：答辩委员会主任签字： 年 月 日学院领导小组综合评定成绩：学院领导小组负责人： 年 月 日摘 要本设计包括三个部分：一般部分、专题部分和翻译部分。一般部分为潘三矿1.8Mt/a新井初步设计，共分10章：1.矿区概述及井田地质特征；2.井田境界和储量；3.矿井工作制度、设计生产能力及服务年限；4.井田开拓；5.准备方式采区巷道布置；6.采煤方法；7.井下运输；8.矿井提升；9.矿井通风与安全技术；10.矿井基本技术经济指标。潘三矿位于安徽省淮南市西北部的淮河北岸，东南距淮南市洞山约34公里。地处凤台县城正北，相距县城15公里左右。行政区划属淮南市潘集区所管辖，井田范围地跨潘集、芦集、田集、贺疃四个乡。潘三矿濒临淮河，东起自第九勘探线与潘一矿相毗邻，西至第十五勘探线和丁集勘探区相邻，矿井北部以F1断层作为与未来的潘四矿之分界线，南部以13-1煤层-900m水平的底板等高线作为深部的井境界，矿井东西走向长约9.3km，南北倾斜宽约5.8km，面积约54km2。矿区铁路专用线与阜淮线、淮南线连接，向东南经合肥至芜湖，可延伸至沪杭、皖赣线，向西约90公里经阜阳至京九线各站，公路30公里与206国道相接。水运由淮河进入长江，在淮河建有自营码头，专门从事煤炭的水运业务。煤炭主要销往淮南平圩与洛河电厂及江浙一带，交通十分便利。矿井最大涌水量为1000m3/时，正常涌水量为700 m3/时；煤质为气煤；全矿井最大绝对瓦斯涌出量为50 m3/min，属高瓦斯矿井；煤层具有一定的自燃发火危险性，自然倾向性等级为级，煤尘具有一定的爆炸危险性。矿井采用立井单水平上下山开拓，采用中央并列式和两翼对角式混合通风。一矿一面，采煤方法为长壁综采一次采全高开采。煤炭运输采用阻燃胶带和底卸式矿车，辅助运输采用蓄电池电机车牵引矿车。矿井年工作日为330 d，每天净提升时间16 h。矿井工作制度为“三八”制。专题部分题目是浅析深井巷道支护技术。翻译部分是一篇关于煤与瓦斯突出矿井无人工作面开采保护层的论文，英文原文题目为：Study on mining the protective seam with the manless working face in coal and gas outburst mines。 关键词：立井；采区；综采；中央并列式；两翼对角式 AbstractThis design includes of three parts: the general part, special subject part and translated part.The general part is a new preliminary design of Pansan wells that annual output is 1.8Mt . The design includes ten chapters: 1. Mine and mine geological features outlined; 2. Waida realm and reserves; 3. Mine system, design capacity and length of service; 4. Waida develop ; 5. to prepare the way - with the district roadway layout; 6. mining methods; 7. underground transport; 8. mine hoist; 9. mine ventilation and security technologies; 10. mine the basic technical and economic indicators.Pansan Mine located in the northwest of Huainan City Anhui Province Huaihei River, south-east of Huainan City Dongshan from about 34 km. Is located in Fengtai County, due north, about 15 km away from town. An administrative division under the jurisdiction of Huainan City area, Ida range across Panji, Luji, Tianji and Hetuan.Pansan Mine the verge of the Huaihe River, the east from the 9th line and the Panyi Mine adjacent to the west, the 15th exploration lines and the small set of exploration area adjacent to the north F1 fault as mine and mine of the future four-line Pansi Mine , 13-1 coal-900m south to the level of bottom contour as the realm of deep wells, mines east-west length of about 9.3km, North-south tilt width of 5.8km, an area of about 54km2.Mine special railway line and the Fuyang-Huainan, Huainan cable connection, to the southeast by the Hefei-Wuhu, can be extended to Hangzhou, Anhui and Jiangxi line, about 90 kilometers west to Beijing-Kowloon line by the Fuyang stations, highways and 206 national highway 30 km phase. Shipping from the Huaihe River into the Yangtze River, Huaihe River built in the self-terminal, specializing in coal shipping business. Huainan coal are sold to power plants and Zhejiang area, the traffic is very convenient. Mine the maximum discharge is 1000m3/h, the normal discharge is 700 m3/h; coal to gas coal; all mine gas emission in the absolute maximum for the 50 m3/min, a high-gas mines; coal has a certain risk of spontaneous combustion , and the natural tendency of grade and coal dust explosion has a certain risk.Mine uses shaft single the level of development and uses Central parallel and the two wings of the roles of ventilation.Side of a mine ，mining method for a fully mechanized longwall mining height. Coal Transportation by the end of flame-retardant tape and bottom dump car . Auxiliary transport uses battery Locomotive traction tramcar.Mine is working days for 330 days, the net every day to enhance the time 16 hours. Mine system is 38 structure.Special subject part is about the research of Deep roadways Supporting Technology. Translation part of an article on mining the protective seam with the manless working face in coal and gas outburst mines.the original English text of the title: Study on mining the protective seam with the manless working face in coal and gas outburst mines.Key words: shaft; panels; fully mechanized mining; central parallel; Wings diagonal ventilation编号：（ ）字 号本科生毕业设计（论文）潘三矿1.8Mt/a新井初步设计韩效辉 01060099采矿06-4班题目： 姓名： 学号： 班级： 二一年六月中 国 矿 业 大 学本科生毕业设计姓 名： 韩效辉 学 号： 01060099 学 院： 矿业工程学院 专 业： 采矿工程 设计题目： 潘三矿1.8Mt/a新井初步设计 专 题： 浅析深井巷道支护技术 指导教师： 常庆粮 职 称： 讲师 2010年6月 徐州中国矿业大学毕业设计任务书学院 矿业工程学院 专业年级 采矿工程06级 学生姓名 韩效辉 任务下达日期：2009年 3月1日毕业设计日期： 2009 年 3月1日至 2009年6月15日毕业设计题目：潘三矿1.8Mt/a新井初步设计毕业设计专题题目：浅析深井巷道支护技术毕业设计主要内容和要求：毕业设计主要内容包括一般部分、专题部分和翻译部分。还要绘制五张大图，分别为矿井开拓平面图、矿井开拓剖面图、采区巷道布置平面图、采区巷道布置剖面图、采煤方法图。一般部分是按潘三矿的实际地质条件，完成潘三矿1.8Mt/a新井初步设计的主要内容，毕业设计一般部分必须按照毕业设计大纲的要求进行，完成大纲规定的全部工程量。毕业设计的专题部分是针对理论上或生产实际中某一具体问题进行较为深入细致的设计和研究。完成这部分内容时，应尽量发挥自己的创造能力，在内容，方法或结论的某一方面尽可能的创新。院长签字： 指导教师签字：中国矿业大学毕业设计指导教师评阅书指导教师评语（基础理论及基本技能的掌握；独立解决实际问题的能力；研究内容的理论依据和技术方法；取得的主要成果及创新点；工作态度及工作量；总体评价及建议成绩；存在问题；是否同意答辩等）：成 绩： 指导教师签字： 年 月 日中国矿业大学毕业设计评阅教师评阅书评阅教师评语（选题的意义；基础理论及基本技能的掌握；综合运用所学知识解决实际问题的能力；工作量的大小；取得的主要成果及创新点；写作的规范程度；总体评价及建议成绩；存在问题；是否同意答辩等）：成 绩： 评阅教师签字： 年 月 日中国矿业大学毕业设计答辩及综合成绩答 辩 情 况提 出 问 题回 答 问 题正 确基本正确有一般性错误有原则性错误没有回答答辩委员会评语及建议成绩：答辩委员会主任签字： 年 月 日学院领导小组综合评定成绩：学院领导小组负责人： 年 月 日摘 要本设计包括三个部分：一般部分、专题部分和翻译部分。一般部分为潘三矿1.8Mt/a新井初步设计，共分10章：1.矿区概述及井田地质特征；2.井田境界和储量；3.矿井工作制度、设计生产能力及服务年限；4.井田开拓；5.准备方式采区巷道布置；6.采煤方法；7.井下运输；8.矿井提升；9.矿井通风与安全技术；10.矿井基本技术经济指标。潘三矿位于安徽省淮南市西北部的淮河北岸，东南距淮南市洞山约34公里。地处凤台县城正北，相距县城15公里左右。行政区划属淮南市潘集区所管辖，井田范围地跨潘集、芦集、田集、贺疃四个乡。潘三矿濒临淮河，东起自第九勘探线与潘一矿相毗邻，西至第十五勘探线和丁集勘探区相邻，矿井北部以F1断层作为与未来的潘四矿之分界线，南部以13-1煤层-900m水平的底板等高线作为深部的井境界，矿井东西走向长约9.3km，南北倾斜宽约5.8km，面积约54km2。矿区铁路专用线与阜淮线、淮南线连接，向东南经合肥至芜湖，可延伸至沪杭、皖赣线，向西约90公里经阜阳至京九线各站，公路30公里与206国道相接。水运由淮河进入长江，在淮河建有自营码头，专门从事煤炭的水运业务。煤炭主要销往淮南平圩与洛河电厂及江浙一带，交通十分便利。矿井最大涌水量为1000m3/时，正常涌水量为700 m3/时；煤质为气煤；全矿井最大绝对瓦斯涌出量为50 m3/min，属高瓦斯矿井；煤层具有一定的自燃发火危险性，自然倾向性等级为级，煤尘具有一定的爆炸危险性。矿井采用单水平上下山开拓，采用中央并列式和两翼对角式混合通风。一矿一面，采煤方法为长壁综采一次采全高开采。煤炭运输采用阻燃胶带和底卸式矿车，辅助运输采用蓄电池电机车牵引矿车。矿井年工作日为330 d，每天净提升时间16 h。矿井工作制度为“三八”制。专题部分题目是浅析深井巷道支护技术。翻译部分是一篇关于煤与瓦斯突出矿井无人工作面开采保护层的论文，英文原文题目为：Study on mining the protective seam with the manless working face in coal and gas outburst mines。 关键词：立井；采区；综采；中央并列式；两翼对角式 AbstractThis design includes of three parts: the general part, special subject part and translated part.The general part is a new preliminary design of Pansan wells that annual output is 1.8Mt . The design includes ten chapters: 1. Mine and mine geological features outlined; 2. Waida realm and reserves; 3. Mine system, design capacity and length of service; 4. Waida develop ; 5. to prepare the way - with the district roadway layout; 6. mining methods; 7. underground transport; 8. mine hoist; 9. mine ventilation and security technologies; 10. mine the basic technical and economic indicators.Pansan Mine located in the northwest of Huainan City Anhui Province Huaihei River, south-east of Huainan City Dongshan from about 34 km. Is located in Fengtai County, due north, about 15 km away from town. An administrative division under the jurisdiction of Huainan City area, Ida range across Panji, Luji, Tianji and Hetuan.Pansan Mine the verge of the Huaihe River, the east from the 9th line and the Panyi Mine adjacent to the west, the 15th exploration lines and the small set of exploration area adjacent to the north F1 fault as mine and mine of the future four-line Pansi Mine , 13-1 coal-900m south to the level of bottom contour as the realm of deep wells, mines east-west length of about 9.3km, North-south tilt width of 5.8km, an area of about 54km2.Mine special railway line and the Fuyang-Huainan, Huainan cable connection, to the southeast by the Hefei-Wuhu, can be extended to Hangzhou, Anhui and Jiangxi line, about 90 kilometers west to Beijing-Kowloon line by the Fuyang stations, highways and 206 national highway 30 km phase. Shipping from the Huaihe River into the Yangtze River, Huaihe River built in the self-terminal, specializing in coal shipping business. Huainan coal are sold to power plants and Zhejiang area, the traffic is very convenient. Mine the maximum discharge is 1000m3/h, the normal discharge is 700 m3/h; coal to gas coal; all mine gas emission in the absolute maximum for the 50 m3/min, a high-gas mines; coal has a certain risk of spontaneous combustion , and the natural tendency of grade and coal dust explosion has a certain risk.Mine uses shaft single the level of development and uses Central parallel and the two wings of the roles of ventilation.Side of a mine ，mining method for a fully mechanized longwall mining height. Coal Transportation by the end of flame-retardant tape and bottom dump car . Auxiliary transport uses battery Locomotive traction tramcar.Mine is working days for 330 days, the net every day to enhance the time 16 hours. Mine system is 38 structure.Special subject part is about the research of Deep roadways Supporting Technology. Translation part of an article on mining the protective seam with the manless working face in coal and gas outburst mines.the original English text of the title: Study on mining the protective seam with the manless working face in coal and gas outburst mines.Key words: shaft; panels; fully mechanized mining; central parallel; Wings diagonal ventilationStudy on mining the protective seam with the manless working face in coal and gas outburst minesFang Xin-qiua,b, Zhao Jun-jiea,b, He Jiea,b, aSchool of Mines, China University of Mining & Technology, Xuzhou 221116, China bState Key Laboratory of Coal Resources and Safety Mine, Xuzhou 221008, ChinaAbstract: In order to solve the problems of backward equipments, low recovery, security issues, high mortality in the coal industry, the technology of manless working face in mine which combined the traditional mining process with the automatic technology is proposed based on the scientized mining, meanwhile, the idea of exploiting the protective seam in the coal seam group of the coal and gas outburst mines with manless working face technology is also proposed so as to liberate other high gas coal seams. Then, making the third coal seam in Shaqu coal mine which is a coal and gas outburst mine as the protective seam was being exploited and carried out the designs which included roadway, equipments selection and mining process. Finally, based on the theoretical analysis and numerical simulation, the gas extraction arrangements is designed, which provides the scientific basis and method for industrial experiment of the third coal seam.Key words: scientized mining; coal seam group; protective seam; manless working face; gas extraction1. IntroductionThe scientized mining means mining the coal with the highest efficiency on the precondition of safety and environment friendly 1. Chinas coal output is very big, the advanced mining machines must be used in order to adapt to the construction of modern mine, furthermore, the manless working face should also be used in some difficult conditions such as thin coal seam or coal and gas outburst seam. Although the mining technology develops rapidly, the overall level is still relatively backward. In order to solve this problem, change the present situation and keep the sustainable development of coal resources 2, the author proposes that the protective seam is mined with the manless working face in the coal and gas outburst mines. Then other high-gas coal seams can be liberated and the gas concentration can also be decreased, so there will be a safe condition for mining. Finally, the safe and high efficient green mining will be achieved 3.2. Mining the protective seam in high outburst minesThe coal seam group is one character of the high gas mining area in china and the permeability of coal seam is very low 4. Therefore, gas is the primary factor which prevents this kind of mines from safety and high efficiency.The protective seam mining is widely used in these high outburst mines in China so as to solve this problem. In addition, this is the most scientific method to prevent the regional gas outburst under the condition of mining the coal seam group in high outburst mines 5, 6.When there is a coal seam group in the gas outburst mine, the no-outburst seam or little-outburst seam will be firstly exploited, and this kind of coal seam is called the protective seam. The original equilibrium state of stress will be broken after the protective seam is exploited. Besides, with the development of roof and floor, the strata stress will be redistributed. The roof strata can be divided into caving zone, fractured zone, and bending zone 7, the floor strata will generate floor heave and fractures 8. The fractures contain bedding joint and cross-fracture, the degree of the fracture development of the floor is in inverse proportion to the spacing of layers. The methods of gas extraction can be classified as short distance, medium distance and long distance through the relative spacing of layers which is based on the concrete geological conditions of the coal mines 9, which provides a theoretical guidance to the gas control of coal seamgroup. The practice of mining the protective seam shows that the gas permeability of the upper outburst-relieved seam increases 1000-3000 times, while that of the lower outburst-relieved seam increases about 1000 times. This provides a good chance for gas extraction. So the effect of the increased gas permeability should be fully utilized to extract the gas by arranging kinds of drillings or roadways which not only ensures the safety of mines but also guarantees the extracted green and efficient gas energy for industry. Then the simultaneous extraction of coal and gas can be realized. The concrete methods are as follows:(1) Extracting the gas by ground surface drilling. This method is applied successfully in America 10, besides,Huainan, Huaibei, and Tiefa mining bureaus also made some tests or applications 11. Although they have got some effect, the stability of the drillings are not very well so that they are broken before the expected life for the different geological conditions between China and America and the influence of the movement of the overlying strata.(2) Arranging some drillings and roadways in the coal seam or strata to extract the gas which is the main method widely used in solving the gas outburst problem.3. Analysis of the feasibility and application in manless working face3.1. Analysis of the feasibilityThe modern manless working face is proposed with the principle of scientized mining and comprehensive utilization of coal resources 12. Based on the concrete conditions of China, we analyze the feasibility of manless working face:The gas emission of the thick and medium-thickness coal seam is more thinner than coal seam, so the thin coal seam is the first choice as protective seam. At present, although the mining degree of chanization and automationin thick and medium-thickness coal seam is relatively high, but in thin coal seam is relatively backward. Blasting mining is the main method of mining the thin coal seam, on the one hand, the mining production rate is low and the partial coal resource is lost 13. On the other hand, the working environment is bad and the labor intensity is big.Considering these unfavorable factors, many coal mines give up exploiting the thin coal seams. This action not only wastes the coal resources seriously but also shortens the service life of the mines, meanwhile, it also restricts the development of the protective seam in the coal seam group of the coal and gas outburst mines. So the urgent affair in mining field is to develop the high yield and high efficiency mining technology.Based on the system model of the manless working face, we make some integrated innovations on the modern technology and analyze the needed technology of every subsystem such as self-positioning and automatic navigationtechnology of the shearer, automatic vertical steering technology of the shearer, automatic recognition technology between coal and strata, electro-hydraulic control technology of the hydraulic support, automatic traction technology of the scraper conveyor, two-way communication technology of high-speed in the underground, component based coalmine software as well as the model technology, database technology and multi-sensor technology.After being combined with these technologies, the manless working face technology can greatly improve the mining rate and promote the security.Coal is the main energy resource in China, the healthy development of the coal industry is related to the energy security and economic sustainable development of China. The coal is non-renewable resource and the service life of the mine is certain. If the thin coal seam can be exploited through the existing production system, the recoverable reserves will be increased, and then the economic benefit will also be increased.At present, gas explosion has the highest proportion in all kinds of the coal mine accidents in China. There were 182 coal mine accidents in 2008, the death toll was 778. So the preventing of gas accidents shoulders heavy responsibilities.3.2. ApplicationBased on the scientific mining, exploiting the protective seam with manless working face is proposed combined with these analyses in coal seam group of the coal and gas outburst mines. After the gas in the coal seam group is released, it can be extracted by the reasonable drillings. It is a win-win method, not only will the frequent gas overrun, frequent gas accidents and the limitation of scale be solved, but also the problems of great difficulty in mining and low mining rate. Furthermore, the green mining of coal resources can be realized by simultaneousextraction of coal and gas.4. Example of mining designs in manless working face4.1. Condition of text areaThe Shaqu coal mine of the HUAJIN coking-coal company is a coal and gas outburst mine. The absolute outflow of gas is 344.43 m3/min and the relative outflow of gas is 61.8 m3/t. It is a short distance coal seam group and the minable seams are the second, third, forth and fifth coal seam (Fig.1).Fig. 1. Columnar section of coal and strata seamThe article 193 of coal mine safety regulation prescribes that the protective seam should be exploited preferentially when mining the coal seam group in coal and gas outburst mine. The article 198 prescribes that the gas of liberated seams should be extracted when mining the protective seam 14. So the Shaqu coal mine constitutes the regional gas government which the third coal seam is mined to liberate the second and third coal seam in order to guarantee the safety and efficient mining.4.2. Design of the working faceThe 13301 working face of Shaqu coal mine is chosen as the experimental area where U-type ventilation is designed in line with reducing the amount of roadway as well as decreasing the gas concentration. In order to extract the gas of 13301 working face, the inclined dense drillings are bored in the return airway by the ADR 250 High-Efficiency drilling rig (Fig.2).Fig. 2. Schematic diagram of gas extracting drilling in 13301The aperture of the drilling rig is 250 mm and its very rare home and broad. The big aperture which is beneficial to extract the gas can greatly improve the extraction rate. The length of the working face is 150 m and the length of the drilling is 140 m, arranging the drilling every 6 m in the direction of tendency and all the drillings are parallel.The distance between open-off cut and the first drilling is 15 m and the last one is at the stopping line, so there are altogether 160 drillings. Using the spiral-welded steel pipe as the main pipe which is laid along the floor and UPVC as the branch pipe which is suspended from the roof, the size of the former is DN820mm12mm and the latter is D225mm10mm. The connection model is flange joint.The shape of the roadway is rectangle using the combined support of anchor, metal net and W-type steel band to support the roadway. Both the width of the conveyance roadway and return airway is 4.5 m, the height of the roadway is 2.8 m.4.3. Selection of the equipments in the working faceChoice of shearerFully automatic mining system of the plough is an effective way to realize high production and efficient 15. The features of little depth-web, fast advance speed and high adaptability make it the first choice in mining the thin coal seam. In order to realize the high production, high efficient and high automation, the GH9-34ve/4.7 plough of the DBT Company is selected combined with the concrete conditions in Shaqu coalmine. The rated power of this plough is 160/315 kW and the production capacity is 900 t/h. It can meet the requirement of high production and high efficient.Choice of hydraulic supportFollowing the principle of reliable system and the priority of domestic equipment, we select the Germany PM4 control unit combined with the domestic hydraulic support. The concrete type is ZY4800/6.5/16.5D of the middle hydraulic support and ZZ5800/16/30 of the terminal hydraulic support. Choice of scraper conveyorThe current proportion between the scraper conveyor and shearer is 1.21.4:1. In order to exert the capacity of the scraper conveyor, we select the PF2.30/732 scraper conveyor.The capacity of the fully mechanized mining equipments should be based on the capacity of the shearer.Meanwhile, the principles of the speed-matching, connection-matching, etc. should also be taken into consideration.Then the main equipments of the working face can be determined (Table 1).Table 1. Main equipments of the working faceEquipment nameTypePloughGH9-34ve/4.7scraper conveyorPF2.30/732Middle hydraulic supportZY4800/6.5/16.5DTerminal hydraulic supportZZ5800/16/30Transfer machineSZZ764/132CrusherPEm1000650Belt conveyorSSJ1200/m4.4. Mining technologyBy means of the combined auto-control shearer and hydraulic support, the automatic coal cutting, automaticadvancing support and the linkage of the scraper conveyor can be realized, meanwhile, using the centralized control and sequential start-stop to realize the automatic control (Fig.3).Fig. 3. Technological process4.5. Design of gas extraction4.5.1. Numerical simulationThe numerical simulation software UDEC is adopted to provide the theoretical basis for the gas extraction so that the gas outburst of the first mining seam and the contiguous seams can be governed well. Taking the strike sectionof the 13301 working face as field model, then, the numerical model can be built length of tendency length of inclination=25055 m, the elevation of the third coal seam is 450 m. The left hand, right hand and lower boundaries of the model are displacement boundary. The left and right boundaries constrain the displacement in x-direction and the lower boundary constrains the displacement in y-direction (Fig.4).Fig. 4. Simulation modelThe change law of the mining influence, height of fractured zone in the roof and floor and the change law of fractured zone with the advancing of working face are simulated in this numerical simulation. The results are as follows:When the advance distance is 40 m (Fig.5), basic roof begins to collapse. The height of the caving zone is about 6m and the strata near basic roof are destroyed by tension. The vertical fracture and interlayer fracture are generatedin the overlying strata and the height of breaking though fracture is about 10 m. There is some deformation in floor of the goaf, which can be seen from the displacement curve of the floor that the maximum compression deformation is 7 m around the lateral of cutting hole and 7 m around the front of the working face. The maximum floor heave deformation is 5 m around the medial of the cutting hole and 5 m around the rear of the goaf. The maximum deformation is 30 mm. When the advance distance is 60 m (Fig.6), the overlying strata and floor strata are destroyed by the interaction of principal stress and shear stress, moreover, the vertical fracture and interlayer fracture develop constantly. With the advancement of the working face, interlayer fracture is the main fracture above the basic roof of the goaf. The main range of vertical fracture is 5 m away from the roof and floor.Fig. 5. Movement status and fracture distributionof surrounding rock (a) when the excavation distance is 40 m; (b) when the excavation distance is 60 m4.5.2. Design of the gas extraction arrangementIt can be obtained from the theoretical analysis and numerical simulation that the second coal seam is in the fractured zone of the third coal seam and the forth coal seam is in the deformation zone of the third coal seam. So the gas can be largely extracted after arranging some drillings in the fractured zone of the roof and deformation zone of the floor.The DDR1200 directional drilling rig which introduced by the Shaqu coal mine can be controlled artificially to drill along the roof or floor at some angle. The aperture is 170 mm and the drilling length is 1200 m. The 13301 working face is selected as the experimental area and the concrete schemes are:Four drillings were born when they reached the forth coal seam, then, boring in the forth coal seam. These drillings can extract the pressure relief gas of forth coal seam and the gas between the third and the forth coal seam.Four drillings were born when they reached the upside of the second coal seam and the vertical distance between the second coal seam and the drillings is 3 m, then, bore along the direction of parallel to second coal seam.So the second coal seam can be liberated. The profile drawing of the drillings is shown in Fig.7.So the coal seam group can be liberated and the problem of gas outburst can also be well solved.Fig. 7. Schematic diagram of profile in 133015. ConclusionsThe problems of coal mining in China are researched and the manless working face is proposed, which is based on the automatic conditions of fully mechanized mining coal face ,It is an important way to realize the sustainable development of coal industry.The idea of mining the protective seam with the manless working